Two new closely related species of Pseudocercospora on unrelated host families from south-eastern Australia.

A species of Pseudocercospora causing foliar lesions on Hibbertia aspera (Dilleniaceae) is morphologically indistingushable from a species of Pseudocercospora causing foliar lesions on Platylobium formosum (Fabaceae) from the same locality. In order to assess the degree to which these fungi were related, we sequenced the ribosomal DNA ITS region of cultures derived from single conidial isolates. Cultures were obtained from four specimens of each respective host. The ITS sequences for cultures derived from the same host were identical, with the exception of one isolate that had a 4 bp insert, while the Pseudocercospora species from Hibbertia consistently differed at three bases from the species isolated from Platylobium. These data suggest that two distinct species of Pseudocercospora are represented, and that they probably result from a recent evolutionary divergence. P. platylobii and P. hibbertiae-asperae spp. nov. are described and illustrated.